Setting and binding material from residues of hydrofluoric acid manufacture



Patented Aug. 26, 1952 RESIDUES MANUFACTURE Q J' ihis, isiaffcontinuatio" "-in partib m "aijfiucai' PATENT f' [ff 2,ss,491 V i I 1' SETTING AND BlNDING MATERIAL FROM on HYDROFLUOBICI ACID 7 V Herman Weber, Harrinian, I f f No Drawing. Application March 25,1949, A

,s riaina sas s a clai (01.106-109) of fluorides and synthetic cryolite from fluorspar. Materials of this kind contain jsapmaiorj-im gradient anhydrous calcium sulphatedsynthetic anhydrate) and other ingredients resulting from said manufacture, for instance" small amounts of sulph 'ric acid and hydrofluoric acid. r J I he -object of my invention is to provide a einentitious composition of inat'ter which utilizes materials of this kindin such a manner that a minimum of treatment and handling of the mate- "is necessary. I

t is-anotherobject of the a ,cementitious material capablejiof setting "and forming products having compr'essivestrengths equal to or greater than any other cementitious materials based on calcium sulphate.

Other objects and advantages and uses of the process and products according to this invention will become apparent from the following specification thereof.

The cementitious material according to this invention is prepared by adding an accelerator to the starting material.

It has been found that plasters of the accelerated anhydrite type can be prepared by using cement, preferably Portland cement, as'an accelerator.

No other treatment of this starting material is necessary to produce products which set perfectly after the addition of water thereto, nor will it be necessary to add other accelerators to the raw material.

It has been found that fresh residue resulting from the fluoride and the cryolite process, as well as the material from the waste pile can be used as the starting material, according to my invention.

In carrying out my invention, the residue calcium sulfate (CaSO4) containing varying small amounts of sulfuric acid (E2804) and hydrofluoric acid (HE) is neutralized with limestone dust (CaCOa), ground to pass an 80 mesh sieve, and mixed with 3-5% Portland cement, which serves as an accelerator, to make the cementitious material.

If the residue has been neutralized by weathering on exposed dumps, no treatment with limestone dust is necessary. Products prepared from these cementitious materials have desirable properties equal to or better than similar products prepared from plaster of Paris, manufactured by calcining gypsum.

vention to'lprovide known plasters.

The compressive streng'thof the product will be after 28 days 3500+ pz-in'c' 'ififresh jstartin material is used, and 2500+2 p. inch fijafter 28 daysif old -material from the dumpsis used.

The cementitious compositions of the invention may'be used for the same purposes as previously They can be usedas cementitious binders for moulding set masses, as, plaster floors (Estrick); wall plasters, decorative plasters, and so forth. 1

To confer special properties, modifying agents may e add eeomn t o aas" Pi 'iQF i IIa i 'JJ 1 gfl pa eror textile fibers, and so forth" materials are preferably mineralize diluted water glass. l

Sand can be added up to 1 to 3. 1 l

3 Articles, for l instance stones} f manufactured Formula 1 .--As a neat mixture usable for inside work only as solid partition blocks, bricks, plates. and floors, and as finish coat plaster, etc.:

By weight:

100 parts cementitious material 18-28 parts water Pounds Iper Square Inc After 7 days 28 days Compression Resistance 2, 500+ 3, 500+ Tensile Strength r 300+ Hardness=3.

Formula 2.-For use as first coat plaster or mortar (1:1):

By weight:

parts cementitious material 100 parts fine sand 40 parts water Pounds per Square Inch After,

7 days 28 days Compression Resistance 1,800 2, 500 Tensile Strength i 250i 3 Formula 3.For use as second coat plaster or mortar (1:2):

By weight:

100 parts cementitious material fl 'na ts flu i and 45: parts water Pounds per Square 1 1. 12 2 cit Com ression Resistance Tens e Strength mortar (1:3):

By weight:

= 100: parts.:cementitious -m8 rial 3nopartstflnersand.

Bounds per Square. 1 med ate Compression Resistance T 125F 95?- a .it a s l i a irc .61. glas 7. iji ideisretc-i ca be, added ice-sp cimen- 1 e se ganic material fter, mnemlizing such'with sodium silicate.

I claim:

154. new: nh drq s quicketti g mater Wis: fifi-n y rou d: n uim iz dertiflcia Formula 4.--For use as base coat plaster or ,anhydrit-e resulting from the process of producing fluorine by the decomposition of fiuorspar with concentrated sulfuric acid, and 3-5% 01' hydraulic cement.

Th pr ces of manuf ctur ng.- an ydrous setting and bindingmaterial'oonsisting in adding an amount of 35% by weight of an hydraulic cement to neutral or neutralized residues resulting from the process of producing fluorine by the decomposition of fluorspar with con REEERENQES; c rca The following references 1area vl of i the file of-this patent:

W nn STATES Number Name,-

, 1,951,691 Q xcn 15 212,527:- Le ehure s- 9. CE P EN S Number Country 1.385

4, 7- Era e -c. L 21 401,19Q Germany 924 600 Germany -.-V M2 4; 

1. A NEW ANHYDROUS QUICK-SETTING MATERIAL CONSISTING OF FINELY GROUND NEUTRALIZED ARTICFICIAL ANHYDRITE RESULTING FROM THE PROCESS OF PRODUCING FLUORINE BY THE DECOMPOSITON OF FLUORSPAR WITH CONCENTRATED SULFURIC ACID, AND 3-5% OF HYDRAULIC CEMENT. 